1. Field of the Invention
This invention relates to a display apparatus, especially to a panel driving circuit and a ring oscillator clock automatic synchronization method thereof.
2. Description of the Related Art
In conventional LCD display apparatus, the panel driving circuit of the panel includes driving ICs coupled in series, and each driving IC is integrated with a timing controller and includes a ring oscillator to provide clock for the gate/source control signals.
In practical applications, in order to make all gate/source outputs achieve synchronization, the ideal condition is that all ring oscillators in the driving ICs have the same frequency. However, since the ring oscillators in the driving ICs cannot be all the same due to the process differences, the display quality of the LCD display apparatus would be poor due to vertical blocks or horizontal blocks shown on the screen of the LCD display apparatus.
Therefore, the invention provides a panel driving circuit and a ring oscillator clock automatic synchronization method thereof to solve the above-mentioned problems occurred in the prior arts.